1. Field of the invention
Double glazing units comprising two sheets of glass secured together in spaced, sealed relationship are increasingly being used to provide thermally insulated windows. A widely used method of making such units is to provide a spacer, usually a metallic channel member, between two sheets of glass in a relation providing a shallow trough around the margins of the assembled panes and to fill this trough with a curing type sealant which commonly is a mixture of a polysulfide polymer and an epoxy resin. When cured this sealant provides a bond holding the assembly together and prevents entry of moisture or dust into the space between the panes of glass. However, this sealant material is expensive and must be carefully compounded in order to remain in place during the time required for the sealant to gel to a condition in which it does not flow out of the desired relationship to the assembly. Also it requires a lengthy period, up to 48 hours before the cure of the sealant has proceeded to a point enabling the assembly to be handled without damaging the joint.